Lady Gaga has canceled the rest of her tour because of a hip injury.

Live Nation Global Touring said Lady Gaga has a tear in her right hip that will require surgery, followed by a recovery period.

The singer’s show is high energy with nonstop dancing.

The pop star’s website showed 21 dates through March 20 remaining on her “Born This Way Ball” tour. Fans who already bought tickets will receive a refund.

Lady Gaga postponed four dates on Tuesday after experiencing difficulties during her Monday concert in Montreal.

A news release announcing postponements Tuesday said the 26-year-old singer, whose real name is Stefani Germanotta, was suffering from synovitis, an inflammation of the joints. She underwent tests Wednesday morning that showed she had a labral tear in her right hip, however. The labrum is a layer of muscle that helps holds the ball-shaped hip joint in place.